please help me! i dont want to ruin my amp!

[animus.terry005]

just bought a Trace Elliot ah250 and it is 4ohm, it has the matching 4ohm cab with it 4x10. i have a hartke cab with 1x15, 2x10s, and a horn. it is an 8ohm cab.
would it be safe to hook up my hartke to the trace?
i dont want to mess it up

[jelwood]

Hook up the head to the 8 ohm cab...you'll be fine. Just don't hook up BOTH cabs to it at once. Simple.

[animus.terry005]

crap, that was why i was wondering. then i need another4ohm cab to hook two up together?
thanks

[JimmyM]

nope, a 4 and 8 ohm cab would make 2.66 ohms, which is below the 4 ohm minimum. it also wouldn't make good sense even if the amp would take it, as the the 115 would get 1/2 the power the 410 gets and there would be an enourmous volume imbalance.

[Munjibunga]

Originally Posted by animus.terry005

crap, that was why i was wondering. then i need another4ohm cab to hook two up together?
thanks

No, you need another 8-ohm cab.

[JimmyM]

Originally Posted by Munjibunga

No, you need another 8-ohm cab.

right. you can do two 8 ohm cabs, but not two 4 ohm cabs. two 8 ohm cabs = 4 ohms, which is safe. two 4 ohm cabs = 2 ohms, which isn't.

[animus.terry005]

wait, i would need two 8ohm cabs for a 4ohm head then?

[animus.terry005]

ok, ok. thank you. got it, i just cant ever get the grasp of the math with ohms ha

[somegeezer]

8ohm + 8ohm, single 8ohm or single 4ohm is what you can do.

[JimmyM]

me neither. i just had to memorize the equations and forget about doing the math

[animus.terry005]

i take it bigger 4ohm cabs exist then? and it is safe to put the 1 8ohm cab on the 4 ohm head? im just making sure here, this thing is 15 years old

[animus.terry005]

got it.

[JimmyM]

Originally Posted by animus.terry005

i take it bigger 4ohm cabs exist then? and it is safe to put the 1 8ohm cab on the 4 ohm head? im just making sure here, this thing is 15 years old

yes, you can do higher impedances than the minimum no problem. one 8 ohm's fine. and yep, you can get bigger 4 ohm cabs for sure. most all 810's and 412's are 4 ohms.

[animus.terry005]

know anyone with an 810 for sale? lol

[StuartV]

animus, just to be sure you're clear, what everybody is saying is ONLY for solid state amps. If, someday, you get a tube amp, you should not hook it up to a cabinet that is higher OR lower than what the amp is expecting.

For example, if you had and Ampeg SVT CL, it would not work with one 8 ohm cab. You could use it with two 8 ohm cabs (i.e. 4 ohms combined), but not just one.

[keyboardguy]

From the Carvin website:

SPEAKER COMBINATIONS and OHMS (Ω):
Four x 8Ω cabinets = 2Ω
Three x 8Ω = 2.66Ω
Two x 8Ω = 4Ω
Two x 4Ω = 2Ω
One 8Ω and One 4Ω cabinet = 2.66Ω
Two 8Ω and One 4Ω = 2Ω
One 2.66Ω and One 8Ω = 2Ω
Two x 2Ω = 1Ω
Three x 4Ω = 1.33Ω
Two x 4Ω and One 8Ω = 1.6Ω

Regards,

Mike

[Mr. Foxen]

Since the impedance adding is inverse, might be handy to picture it like fractions of an inch. Like 1/8th of an inch and 1/8th of an inch total 1/4 or an inch.